Shorty header exhaust noise? Header collector Gasket?

I've had my ceramic coated Ebay Powergo shorties with remflex gaskets on for a few thousand miles and they have increased the engine noise considerably more than the stock manifolds. I have verified no easy to find leaks on the collector side but they fit much deeper inside the stock collector flange more than the factory stuff. The noise is louder when cold and it's not really a tick noise as I've had cracked ****** shorties before. This is like its louder when cold started and gets quieter as it heats up to normal temp but on light load no throttle almost no noise. As load increases it gets louder like pressure building up in the exhaust (throttle tip in but no downshift or quick rpm increase) like your loading the engine up. I find it just annoying and was wondering if there is a change I can't "feel" the leak at idle at the collector. I wanted to see if anyone has found a collector gasket to put in there? I have this exhaust paste that seals up when it drys out but its a PITA to remove/scrape out.

Thats not the style on the factory stuff. its a ball/socket style and the header ball is smaller DIA than the factory manifold. I was thinking of something like this and widdle it down maybe depending on material harness to fit.

I tried swapping gaskets and adding copper RTV to the collector on my Kooks to make the noise go away. Pretty sure its just injector noise according to what I've read on here. Since the headers are thinner material than the manifolds you can hear the injectors. I've just learned to deal with it.

joesstripclub said:

I tried swapping gaskets and adding copper RTV to the collector on my Kooks to make the noise go away. Pretty sure its just injector noise according to what I've read on here. Since the headers are thinner material than the manifolds you can hear the injectors. I've just learned to deal with it.

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I’ve done the High temp RTV and it just burns off that close to the head. I had a exhaust paste that worked good but it’s like cement so it’s tough to get off once you put it on.

Well it seems like I fixed it! For all the people who check this in the future this was my fix which I did tonight and started it up and pretty dang quiet Minus the valve train. Took alot of searching to find a gasket that fit my specs and the material I wanted.

I removed the bolts and then took a Mahle donut style gaskets which matched the ID of the collector (2.25”) measurement I got from the manufacture. I took a carbide bit and ground out the inside of the gasket edge (not in the pics) to remove the hard edge and installed. The gasket is a graphite style gasket with a steel core I believe. I wanted the graphite bc of how it seals and withstands super high temps. Lined everything up and tightened it all done and boom no leaks…. Now let’s hope it lasts.

Pics of the gasket and part numbers. This will only work on the power go headers as the collector ball is smaller DIA than stock.

Where did you get the gasket? I can't find anything with that part number. I have the same exhaust leak when under load and this is the first post that someone has solved the issue. I already replaced the manifold gaskets but with no luck. I'm going to try and find this gasket and see if it work with my BBK shorties.

Anyone looking for the gasket it’s part number is Mahle f7549 as seen under / behind the barcode sticker in picture 1

*edit - gasket is too small for oem sized collectors (AFE)